US Patent 10328253 Medical electrical stimulation lead including expandable coiled fixation element

A medical lead includes a coiled conductor portion that defines at least part of an outer surface of the lead and an expandable coiled fixation element that defines at least a part of the outer surface of the lead. The expandable coiled fixation element is configured to expand from a first dimension in a first state to a second dimension in a second state in a direction away from the coiled conductor portion. In some examples, the expandable coiled fixation element comprises a shape memory material.